Communication networks typically contain at least one method with which to interconnect communication devices to allow for end-to-end communication thereon. A network facilitates communication by providing a channel that allows analog and/or digital information to be shared amongst devices connected to the channel. A channel can take various forms, including a shielded wire capable of carrying electronic signals, (e.g., a co-axial cable wire, a copper telephone wire, etc.) or an electromagnetic signal propagating through Earth's atmosphere or through physical structures at various frequencies, (e.g., radio frequencies, microwave frequencies, and optical frequencies).
As the number of communication devices increases, the number of channels, of various forms, required to connect these devices increases as well. Simultaneously connecting large numbers of communication devices has become very costly for communication network service providers. Traditionally, either a physical wire, or portion of its bandwidth, or an electromagnetic frequency channel, and a portion of the equipment required to operate and to separate those channels, must be dedicated to each communication. Because millions of communications occur daily in populated areas of the world, and providing the resources to facilitate those communications is expensive, efforts have been expended to find ways to decrease the resources required to sustain these communication networks.
One solution to decrease the resources required to facilitate mass communication is to perform communication setup and termination procedures, sometimes referred to as initiation or signaling, over separate channels from communication channels. This procedure can be referred to as out-of-band signaling, as the signaling process is performed outside of the channel established for end-to-end device communication. Because the amount of information required for setup and termination is relatively small, a much smaller and less expensive network can provide a platform for these signaling services. One example of a modern signaling system established for the public telephone network is the Signaling System 7 (SS7) network. SS7 and its predecessor systems were initially established on circuit switched telephone networks for network security purposes. However, as mobile and Internet Protocol (IP) networks have begun to connect with each other and with telephone networks, resource-saving signaling networks, including SS7 and mobile and IP protocol counterparts, have become prominent.
In addition to providing security for network signaling procedures and reducing the resources required to setup and terminate communication channels, signaling networks also provide presence information to components connected on a signaling network. Presence information is information that can be obtained through a signaling network when a device first logs onto a communication network. One example of presence information is an indication that a device is ‘present’ on a network and has an ability and willingness to communicate thereon. A common example of presence is illustrated by Instant Messaging (IM) systems. IM devices can display a list of other devices that are logged onto a communication network and ready to begin communication with an IM device user. For example, a friend's list on an IM device can indicate what ‘friends’ of an IM device user are logged onto a network.
Presence information is generally updated and available to a network whenever a device first logs onto a network. Additional presence information can include location information, subscription information, and service information pertaining to each communication device logged onto a network. However, unlike information indicating a device is ‘present’, this information is generally not made available to other users until after communication has been initiated, if at all.